Stitching end effector

ABSTRACT

A stitching assembly includes upper and lower cradles, upper and lower needles, and first and second sutures supported by the upper and lower needles, respectively. The cradles move along a curved path in relation to the carriages between advanced and retracted positions. When each cradle is moved from the retracted position towards the advanced position, a stitch loop is formed when the respective needle is retracted. This process is repeated alternating between the first and second cradles with the upper and lower needles passing through the previous stitch loop formed by the other needle before passing through the tissue.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/507,900, filed Oct. 7, 2014, which claims the benefit of and priorityto U.S. Provisional Patent Application Ser. No. 62/006,922, filed Jun.3, 2014. The entire disclosure of each of the above applications isincorporated by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates to surgical instruments, specifically,surgical instruments with a stitching end effector for forming stitches.

2. Background of the Invention

As medical and hospital costs continue to increase, surgeons areconstantly striving to develop advanced surgical techniques. Advances inthe surgical field are often related to the development of operativetechniques which involve less invasive surgical procedures which reduceoverall patient trauma. In this manner, the length of hospital stays andthus, medical costs can be significantly reduced.

One of the truly great advances to reduce the invasiveness of surgicalprocedures is endoscopic surgery. Endoscopic surgery involves surgerythrough body walls for example, viewing and/or operating on the ovaries,uterus, gall bladder, bowels, kidneys, appendix, etc. There are manycommon endoscopic surgical procedures, including arthroscopy,laparoscopy (pelviscopy), gastroentroscopy and laryngobronchoscopy, justto name a few. Typically, trocars are utilized for creating incisionsthrough which the endoscopic surgery is performed. Trocar tubes orcannula devices are extended into and left in place in the abdominalwall to provide access for endoscopic surgical tools. A camera orendoscope is inserted through a trocar tube to permit the visualinspection and magnification of the body cavity. The surgeon can thenperform diagnostic and therapeutic procedures at the surgical site withthe aid of specialized instrumentation, such as, forceps, cutters,applicators, and the like which are designed to fit through additionalcannulas.

In many surgical procedures, it is often necessary to suture body organsor tissue. Traditionally, suturing was accomplished by hand using aneedle attached to a suture material. This procedure required openaccess to the tissue to be sutured. Upon the advent of endoscopicsurgical procedures, endoscopic suturing instruments have beendeveloped. The development of endoscopic suturing instruments isespecially challenging because of the small openings through which thesuturing of body organs or tissues must be accomplished.

SUMMARY

In an aspect of the present disclosure, a stitching assembly includes anupper cradle, an upper carriage, an upper needle, and a first suture.The upper carriage is configured to support the upper cradle formovement along a curved path between an advanced position and aretracted position relative to the upper carriage. The upper needle issupported by and extends distally from the upper cradle. The firstsuture is supported by the upper needle. The upper cradle and the uppercarriage are configured to draw the first suture through tissue when theupper cradle is moved towards the advanced position and are configuredto form a first stitch loop in the first suture when the upper cradle ismoved from the advanced position towards the retracted position. Inaddition, the stitching assembly includes a lower cradle, a lowercarriage, a lower needle, and a second suture. The lower carriage isconfigured to support the lower cradle for movement along a curved pathbetween an advanced position and a retracted position relative to thelower carriage. The lower needle is supported by and extends distallyfrom the lower cradle. The second suture is supported by the lowerneedle. The lower cradle and the lower carriage are configured to drawthe first suture through tissue and the first stitch loop when the lowercradle is moved towards the advanced position and are configured to forma second stitch loop in the second suture when the lower cradle is movedfrom the advanced position towards the retracted position.

In aspects, the upper needle includes an outer surface and a distal endand the upper carriage includes an upper plow that is positionedadjacent the distal end of the upper needle. The upper plow of the uppercarriage and the outer surface of the upper needle being configured tocapture a portion of the first suture therebetween as the upper cradleis moved towards the advanced position. In addition, the lower needleincludes an outer surface and a distal end and the lower carriageincludes a lower plow that is positioned adjacent the distal end of thelower needle. The lower plow of the lower carriage and the outer surfaceof the lower needle being configured to capture a portion of the secondsuture therebetween as the lower cradle is moved towards the advancedposition.

In some aspects, the upper carriage has a sidewall that defines a camslot and the upper cradle includes a sidewall including a cam. The camof the upper cradle is received within the cam slot of the uppercarriage. The upper needle may be a curved needle. The cam slot of theupper carriage may be a curved cam slot defining the curved path of theupper cradle. A curvature of the curved path of the upper cradle maycorrespond to a curvature of the curved upper needle.

In another aspect of the present disclosure, a stitching loading unitincludes an inner housing, a jaw member assembly, and a stitchingassembly. The inner housing having proximal and distal ends. The jawmember assembly is positioned at the distal end of the inner housing andincludes first and second jaw members. The first and second jaw membersare moveable relative to one another between open and clamped positions.Each of the first and second jaw members define a longitudinal needleslot positioned parallel to the longitudinal axis of the jaw member. Thestitching assembly may be any of the stitching assemblies disclosedherein.

In aspects, the stitching loading unit includes a suture storage anddelivery assembly having a suture tension, a first suture recess, asecond suture recess, a groove, a conduit, a portion of the firstsuture, and a portion of the second suture. The first suture recess isdefined by and along a length of the inner housing, the first suturerecess is positioned proximal to the suture tensioner. The second suturerecess is defined by and along a length of the inner housing proximal tothe first suture recess. The groove is defined in the inner housingthrough the first suture recess and into the second suture recess. Theconduit is disposed within the groove. The portion of the first sutureis wound around the inner housing in the first suture recess, passesthrough the suture tensioner, and through the upper needle. The portionof the second suture is wound around the inner housing in the secondsuture recess, passes through the conduit, passes through the suturetensioner, and passes through the lower needle.

In some aspects, the stitching loading unit includes a drive barassembly that is disposed within the inner housing. The drive barassembly includes an upper carriage drive bar, an upper cradle drivebar, a lower carriage drive bar, and a lower cradle drive bar. The uppercarriage drive bar includes a distal end that is connected to the uppercarriage to move the upper carriage within the upper jaw member. Theupper cradle drive bar includes a distal end that is operativelyassociated with the upper cradle to move the upper cradle between theretracted and advanced positions. The lower carriage drive bar includesa distal end that is connected to the lower carriage to move the lowercarriage within the lower jaw member. The lower cradle drive barincludes a distal end that is operatively associated with the lowercradle to move the lower cradle between the retracted and advancedpositions. A proximal end of the upper cradle drive bar may be disposedover the upper carriage drive bar distal to a proximal end of the uppercarriage drive bar such that the upper cradle is advanced with the uppercarriage. A proximal end of the lower cradle drive bar may be disposedover the lower carriage drive bar distal to a proximal end of the lowercarriage drive bar such that the lower cradle is advanced with the lowercarriage.

In particular aspects, the distal end of the upper cradle drive barincludes a cradle finger that is operatively associated with the uppercradle. In embodiments, the cradle drive finger is flexible. A distalend of the cradle drive finger may be fixed to a surface of the uppercradle such that when the cradle is in the advanced position, the cradledrive finger forms a curve with a surface of the upper cradle. In otherembodiments, the cradle drive finger is substantially rigid. The cradledrive finger may include a toothed rack and a surface of the uppercradle may include a pinion. The toothed rack engages the pinion to movethe cradle between the retracted and advanced positions.

In certain aspects, the stitching loading unit includes an extension rodassembly disposed within the inner housing. The extension rod assemblyincluding an upper carriage extension rod, an upper cradle extensionrod, a lower carriage extension rod, and a lower cradle extension rod.The upper carriage extension rod includes a distal end that isoperatively associated with the upper carriage drive bar tolongitudinally translate the upper carriage drive bar. The upper cradleextension rod includes a distal end that is operatively associated withthe upper cradle drive bar to longitudinally translate the upper cradledrive bar. The lower carriage extension rod includes a distal end thatis operatively associated with the lower carriage drive bar tolongitudinally translate the lower carriage drive bar. The lower cradleextension rod includes a distal end that is operatively associated withthe lower cradle drive bar to longitudinally translate the lower cradledrive bar.

In aspects, the stitching loading unit includes including an I-beam, anda knife defined by the I-beam. The I-beam is positioned within and islongitudinally translatable within a knife slot. The knife slot isdefined about the longitudinal axis of each of the first and second jawmembers. The knife slot extends from the proximal end of each of thefirst and second jaw members and towards a distal end of each of thefirst and second jaw members. The drive bar assembly may include a knifedrive bar that has a proximal end connected to the upper carriage drivebar. A distal end of the knife drive bar is operatively associated withthe I-beam to advance the I-beam with the upper carriage drive bar. Thefirst and second jaw members each define a beam groove in an outersurface of the jaw member. The I-beam may include upper and lowerflanges integrally formed on upper and lower surfaces thereof. The upperand lower flanges may be received within the beam grooves of the upperand lower jaw member to urge the jaw members towards the clampedposition as the I-beam is advanced through the knife slot.

In some aspects, the stitching loading unit includes an articulationassembly having an articulation joint, an articulation pivot, anarticulation rod, and an articulation pin. The articulation joint ispositioned between a proximal end of the jaw member assembly and adistal end of the inner housing. The articulation pivot passes throughthe articulation joint. The articulation pivot is orthogonal to andpasses through the longitudinal axis of the first and second jaw memberswhen the jaw members are in the clamped position. The articulation rodis disposed within the inner housing and includes a proximal end. Thearticulation pin passes through the proximal end of the articulation rodand the articulation joint. The articulation pin is parallel to thearticulation pivot. The articulation joint is offset from thearticulation pivot such that when the articulation rod is longitudinallytranslated, the jaw member assembly articulates relative to the outertube about the articulation pivot.

In still another aspect of the present disclosure, a surgical instrumentfor suturing tissue includes a handle and a stitching loading unit. Thestitching loading unit is operatively associated with the handle. Thestitching loading unit may be any of the stitching loading unitsdisclosed herein.

In aspects, the handle includes a drive shaft for manipulating thestitching loading unit. The surgical instrument may include an adaptorhaving proximal and distal ends. The proximal end of the adaptor engagesthe handle and the distal end of the adaptor receives a connector of thestitching loading unit. The connector is configured to manipulate thestitching assembly of the stitching loading unit. The adaptor isconfigured to convert rotation of drive shafts of the handle tolongitudinal translation to longitudinal translation of the stitchingassembly of the stitching loading unit.

In still yet another aspect of the present disclosure, a stitchingassembly includes a first jaw member, a second jaw member, a firstneedle, a first suture, a second needle, and a second suture. The firstjaw member has proximal and distal ends and the second jaw member hasproximal and distal ends. The first needle is moveable in a stepwisemanner between the proximal and distal ends of the first jaw member. Thefirst needle is moveable between a retracted position, where the firstneedle is disposed within the first jaw member, and an advancedposition, where the first needle is extended towards the second jawmember from the first jaw member. The first suture is associated withthe first needle. The second needle is moveable in a stepwise mannerbetween the proximal and distal ends of the second jaw member. Thesecond needle is moveable between a retracted position, where the secondneedle is disposed within the second jaw member, and an advancedposition, where the second needle is extended towards the first jawmember from the second jaw member. The second suture is associated withthe second needle. In addition, the stitching assembly includes firstand second drive bars. The first drive bar is configured at each step ofmovement of the first needle to move the first needle from the retractedposition to the advanced position and to return the first needle to theretracted position. This movement of the first needle forms a sutureloop in the first suture through tissue and adjacent the second jawmember. The second drive bar is configured to at each step of movementof the second needle to move the second needle from the retractedposition to the advanced position and to return the second needle to theretracted position. This movement of the second needle forms a sutureloop in the second suture through tissue and adjacent the first jawmember.

Further, to the extent consistent, any of the aspects described hereinmay be used in conjunction with any or all of the other aspectsdescribed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of the present disclosure are described herein belowwith reference to the drawings, wherein:

FIG. 1 is a front perspective view of an embodiment of a surgicalinstrument in accordance with the present disclosure including astitching end effector;

FIG. 2 is a rear perspective view of the stitching end effector of FIG.1 with the jaws in an open position;

FIG. 3 is a front perspective view of the stitching end effector of FIG.2 with the jaws in an open position;

FIG. 4 is an exploded view of the stitching end effector of FIG. 2;

FIG. 5 is an enlarged view of the indicated area of detail of FIG. 4;

FIG. 6 is an enlarged view of the indicated area of detail of FIG. 5;

FIG. 7 is an enlarged view of the indicated area of detail of FIG. 5;

FIG. 8 is a front perspective of the drive bar assembly and thestitching assembly of FIG. 5;

FIG. 9 is a cross-sectional view taken along section line “9-9” of FIG.8;

FIG. 10 is an exploded view of the drive bar assembly illustrated inFIG. 5

FIG. 11 is a top perspective view of the upper carriage extension bar ofthe drive bar assembly engaged with the upper carriage drive bars of thedrive bar assembly;

FIG. 12 is an enlarged view of indicated area of detail of FIG. 11;

FIG. 13 is an enlarged view of indicated area of detail of FIG. 2;

FIG. 14 is a cross-sectional view taken along section line “14-14” ofFIG. 2;

FIG. 15 is an exploded perspective view of the knife assembly;

FIG. 16 is a top view of the stitching end effector of FIG. 2 in anon-articulated configuration;

FIG. 17 is a top view of the stitching end effector shown in FIG. 16 inan articulated configuration with a longitudinal axis of the jawassembly of the end effector defining an angle in relation to alongitudinal axis of the outer tube;

FIG. 18 is an enlarged view of the indicated area of detail of FIG. 10illustrating the cradle and the carriage of FIG. 10 with the cradle in aretracted configuration;

FIG. 19 is a perspective view of the cradle of FIG. 18 with the carriageremoved;

FIG. 20 is an exploded view of the carriage and the cradle of FIG. 18;

FIG. 21 is a perspective view of the cradle and the carriage of FIG. 18with the cradle in an advanced configuration;

FIG. 22 is a perspective view of the cradle of FIG. 21 with the carriageremoved;

FIG. 23 is perspective view of another embodiment of a cradle drivefinger in accordance with the present disclosure including a rack andpinion with the cradle in a retracted configuration;

FIG. 24 is a perspective view of the cradle drive finger of FIG. 23 withthe cradle in an advanced configuration;

FIG. 25 is a front perspective view of the stitching end effector ofFIG. 2 with the upper jaw and the outer tube removed;

FIG. 26 is an enlarged view of the indicated area of detail of FIG. 25with the cradles in the retracted configuration and the needles withinthe needle slots of the lower jaw;

FIG. 27 is an enlarged view of the indicated area of detail of FIG. 4 ofthe suture tensioner;

FIG. 28 is a view of the cradles of FIG. 26 in an advanced configurationwith the needles extending from the needles slots of the lower jaw;

FIG. 29 is a cross-sectional view of the stitching end effector takenalong section line “29-29” of FIG. 16;

FIG. 30 is a cross-sectional view of the stitching end effector of takenalong section line “30-30” of FIG. 16;

FIG. 31 is an enlarged view of the indicated area of detail of FIG. 30;

FIG. 32 is a cross-sectional view of the stitching end effectorillustrating the drive bar assembly advanced to a clamped position;

FIG. 33 is an enlarged view of the indicated area of detail of FIG. 32;

FIG. 34-38 are a progression of longitudinal side cross-sectional viewsof the stitching end effector forming first, second, and third stitchloops as the drive bar assembly is manipulated in accordance with thepresent disclosure.

DETAILED DESCRIPTION

Embodiments of the present disclosure are now described in detail withreference to the drawings in which like reference numerals designateidentical or corresponding elements in each of the several views. Asused herein, the term “clinician” refers to a doctor, a nurse, or anyother user, operator, or care provider and may include supportpersonnel. Throughout this description, the term “proximal” refers tothe portion of the device or component thereof that is closest to theclinician and the term “distal” refers to the portion of the device orcomponent thereof that is farthest from the clinician.

Referring now to FIG. 1, an exemplary embodiment of a surgicalinstrument 1 is provided in accordance with present disclosure andincludes a handle 10, a stitching adaptor 20, and a stitching loadingunit 30. The stitching loading unit 30 is configured to provide a lineof stitches along the length of a jaw assembly as will be discussed indetail below. The handle 10 is a powered handle with one or more driveshafts (not shown) that rotate independently of one another. Anexemplary embodiment of such a powered handle is disclosed in commonlyowned and co-pending U.S. patent application Ser. No. 13/484,975 filedMay 31, 2012, and now published as U.S. Patent Publication No.2012/0253329 on Oct. 4, 2012, the contents of which are incorporatedherein by reference in its entirety. It is also contemplated that thehandle 10 may be a manually driven handle with one or more outputshafts.

The stitching adaptor 20 converts rotary motion of the drive shafts ofthe handle 10 into linear motion of selected drive bars to manipulatethe stitching loading unit 30 as detailed below. The stitching adaptor20 may include one or more gear trains (not shown) and one or more camsto convert the rotary motion of the drive shafts of the handle 10 intolinear motion of the drive bars. An exemplary embodiment of such astitching adaptor 20 is disclosed in commonly owned and co-pending U.S.patent application Ser. No. 14/279,928, filed May 16, 2014, nowpublished as U.S. Patent Publication No. 2015/0327850, the contents ofwhich are incorporated herein by reference in its entirety.

With reference to FIGS. 2-4, the stitching loading unit 30 includes anouter tube 32, a jaw assembly 34, and an inner housing 62. A proximalend of the stitching loading unit 30 forms a connector 33 that engagesthe stitching adaptor 20 to secure the stitching loading unit 30 to thestitching adaptor 20.

The jaw assembly 34 includes a first or upper jaw member 36 and a secondor lower jaw member 38. The upper and lower jaw members 36, 38 aremoveable relative to one another between an open configuration (FIG. 3)and a closed or clamped configuration (FIG. 32). The upper jaw member 36defines a longitudinal knife slot 96 a disposed along a longitudinalaxis of the upper jaw member 36. The lower jaw member 38 defines alongitudinal knife slot 96 b disposed along a longitudinal axis of thelower jaw member 38. Each of the knife slots 96 a, 96 b extends throughan inner or tissue contacting surface of a respective one of the jawmembers 36, 38 and an outer surface of a respective one of the jawmembers 36, 38. Each of the knife slots 96 a, 96 b extends along thelongitudinal axis of a respective one of the jaw members 36, 38 from aproximal end thereof to a point adjacent a distal end of the respectivejaw member 36, 38. The outer surface of each of the jaw members 36, 38defines a longitudinal beam groove 98 for receiving an upper or lowerflange 97 of an I-beam 94 (FIG. 33) as detailed below. The beam grooves98 are disposed about the knife slots 96 a, 96 b and extend from theproximal end of each of the jaw members 36, 38 to the distal end of theknife slots 96 a, 96 b.

Each of the jaw members 36, 38 further defines longitudinal needle slots39. The needles slots 39 are disposed in pairs on opposite sides of theknife slots 96 a, 96 b. The needle slots 39 of the lower jaw member 38oppose the needle slots (not shown) of the upper jaw member 36. Thedistal end of each of the jaw members 36, 38 includes a blunt tip 37 andangled guide surface 37 a which are configured to atraumatically contactand guide tissue between the jaw members 36, 38.

The inner housing 62 is generally cylindrical and is disposed within theouter tube 32. The inner housing 62 may include an upper segment 62 aand a lower segment 62 b which are secured together using knownfastening techniques (e.g., welding, gluing, etc.). The inner housing 62slidably receives a drive bar assembly 40 and an extension rod assembly70.

Referring to FIGS. 5-14, the drive bar assembly 40 includes uppercarriage drive bars 41 (FIG. 7), upper cradle drive bars 42 (FIG. 7),lower carriage drive bars 43 (FIG. 10), and lower cradle drive bars 44(FIG. 10). A stitching assembly 80 (FIG. 6) is supported on a distal endof the drive bar assembly 80 and includes upper carriages 44, uppercradles 45, lower carriages 46, and lower cradles 47. Each of the drivebars 41-44 translate longitudinally in a stepwise manner (i.e., in aseries of distinct steps) within the inner housing 62 to actuate theupper carriages 44, upper cradles 45, lower carriages 46, and lowercradles 47 as detailed below.

Each carriage drive bar 41, 43 is positioned adjacent to and flanked byone of the cradle drive bars 42, 44 (FIGS. 9 and 10). A distal end ofeach of the upper carriage drive bars 41 is connected, either rigidly orreleasably, to one of the upper carriages 45 such that longitudinaltranslation of a drive bar 41 effects longitudinal translation of theupper carriage 45 (FIG. 7). Similarly, a distal end of each of the lowercarriage drive bars 43 is connected to one of the lower carriages 47such that longitudinal translation of a drive bar 41 effectslongitudinal translation of the lower carriage 47. In embodiments, thedistal end of each of the upper carriage drive bars 41 is integrallyformed with one of the upper carriages 45 and the distal end of each ofthe lower carriage drive bars 43 is integrally formed with one of thelower carriages 47. The carriage drive bars 41, 43 may be connected tocorresponding carriages 45, 47 in a rigid or releasable manner, forexample integrally formed, snap fit, through glue, welding, molding, orvia any variety of fasteners, or any other technique known to those ofskill in the art.

The proximal ends 41 a of the upper carriage drive bars 41 are connectedto one another and the proximal ends 42 a of each of the upper cradledrive bars 42 are connected to one another (e.g., by welding or gluing)(FIG. 7). Similarly, the proximal ends 43 a (FIG. 14) of each of thelower carriage drive bars 43 are connected to one another and theproximal ends 44 a (FIG. 14) of each of the lower cradle drive bars 44are connected to one another. The proximal ends 41 a, 42 a, 43 a, 44 amay be connected to corresponding proximal ends 41 a, 42 a, 43 a, 44 ain a rigid or releasable manner, for example integrally formed, snapfit, through glue, welding, molding, or via any variety of fasteners, orany other technique known to those of skill in the art.

The proximal ends 42 a of the upper cradle drive bars 42 are positioneddistal to the proximal ends 41 a of the upper carriage drive bars 41such that when the upper carriage drive bars 41 are advanced, theproximal ends 41 a of the upper carriage drive bars 41 engage theproximal ends 42 a of the upper cradle drive bars 42 to advance theupper cradle drive bars 42. Similarly, the proximal ends 44 a of thelower cradle drive bars 44 are positioned distal to the proximal ends 43a of the lower carriage drive bars 43 such that when the lower carriagedrive bars 43 are advanced, the proximal ends 43 a of the lower carriagedrive bars 43 engage the proximal ends 44 a of the lower cradle drivebars 44 to advance the lower cradle drive bars 44. As shown in FIG. 7,the proximal ends 42 a of the upper cradle drive bars 42 may bepositioned over the upper carriage drive bars 41. Similarly, theproximal ends 44 a of the lower cradle drive bars 44 may be positionedover the lower carriage drive bars 43.

As shown in FIGS. 8 and 9, the upper carriage drive bars 41 areconnected to the knife drive member 95 such that longitudinaltranslation of the upper carriage drive bars 41 effects longitudinaltranslation of the knife drive member 95. Alternatively, it iscontemplated that the lower carriage drive bars 43 may be connected tothe knife drive member 95 such longitudinal translation of the lowercarriage drive bars 43 effects longitudinal translation of member 95.The carriage drive bars 41, 43 may be connected to the knife drivemember 95 in a rigid or releasable manner, for example integrallyformed, snap fit, through glue, welding, molding, or via any variety offasteners, or any other technique known to those of skill in the art.

The proximal ends 41 a of the upper carriage drive bars 41 are connectedto an upper carriage drive arm 41 b and the proximal ends 42 a of theupper cradle drive bars 42 are connected to an upper cradle drive arm 42b (FIG. 9). For example, the upper carriage drive arm 41 b may beintegrally formed with a proximal end 41 a of one of the upper carriagedrive bars 41 and the upper cradle drive arm 42 b may be integrallyformed with the proximal end 42 a of one of the upper cradle drive arms42 b. Alternatively, the upper drive arms 41 b, 42 b may be welded orglued to a respective one of the upper drive bars 41, 42. Similarly, theproximal ends 43 a of the lower carriage drive bars 43 are connected toa lower carriage drive arm 43 b and the proximal ends 44 a of the lowercradle drive bars 44 are connected to a lower cradle drive arm 44 b(FIG. 14). The proximal ends 41 a, 42 a, 43 a, 44 a of the drive bars41, 42, 43, 44 may be connected to corresponding drive arms 41 b, 42 b,43 b, 44 b in a rigid or releasable manner, for example integrallyformed, snap fit, through glue, welding, molding, or via any variety offasteners, or any other technique known to those of skill in the art.

With particular reference to FIGS. 10-14, the extension rod assembly 70includes an upper carriage extension rod 72, an upper cradle extensionrod 74, a lower carriage extension rod 76, and a lower cradle extensionrod 78. The distal portion of each of the extension rods 72, 74, 76, 78is engagable with includes an engagement mechanism, such as notch 72 a,74 a, 76 a, 78 a, configured to engage a respective one of the drivearms 41 b, 42 b, 43 b, 44 b such that movement, for example longitudinaltranslation, of the extension rods 72, 74, 76, 78 effects movement, forexample longitudinal translation, of each of the drive bars 41, 42, 43,44, respectively. For example, as shown in FIG. 12, the notch 72 a inthe distal portion of the upper cradle extension rod 72 engages theupper carriage drive arm 41 a to axially fix upper cradle extension rod72 to the upper carriage drive bar 41. The proximal end of each of theextension rods 72, 74, 76, 78 includes an extension wing 72 b, 74 b, 76b, 78 b (FIG. 10) positioned proximal to the proximal end of the outertube 32 of loading unit 30 (FIG. 1) adjacent the connector 33. Theconnector 33 is configured to engage the adaptor 20 such that theadaptor 20 can manipulate the extension wings 72 b, 74 b 76 b, 78 b tooperate the loading unit 30. It is contemplated that the connector 33may engage a handle or robotic controller which is configured tomanipulate the extension wings 72 b, 74 b 76 b, 78 b to operate theloading unit 30.

When the extension rod assembly 70 is assembled within the loading unit30, the extension rods 72, 74, 76, 78 are slidably disposed within theinner housing 62 of the loading unit 30. The extension wings or tabs 72b, 74 b, 76 b, 78 b of the carriage extension rods 72, 74, 76, 78 extendbeyond the outer surface of the inner housing 62 (FIG. 13) to facilitateengagement by the adaptor 20 or other controller. It is alsocontemplated that the loading unit 30 may engage with the adaptor 20 inany manner known to those of skill in the art. For example, the loadingunit 30 may engage with the adaptor 20 by a bayonet-type connection, aJ-hook type connection, a screw type connection, a spring-detentconnection, or any combination thereof. Examples of such connections aredisclosed in U.S. patent application Ser. No. 14/279,928, filed May 16,2014, and U.S. Pat. No. 7,308,998, the contents of each are incorporatedherein by reference in its entirety.

Referring also to FIG. 15, the knife assembly 90 includes an I-beam 94and a knife drive member 95. The I-beam 94 has a vertical strut 97 adefining a knife 92, and upper and lower flanges 97 interconnected bythe vertical strut 97 a. The knife drive member 95 is coupled to aproximal portion of the I-beam 94 to advance and retract the I-beam 94as detailed below. As detailed above, the knife drive member 95 isconnected to the upper carriage drive bars 41 such that the knife drivemember 95 is moved, such as advanced and retracted, in response tomovement, such as advancement and retraction, of the upper carriagedrive bars 41.

Referring to FIGS. 16 and 17, the stitching loading unit 30 includes anarticulation assembly 50 that includes an articulation member 52, amounting member 53, an articulation pivot 54, and an articulation pin56. The articulation assembly 50 is configured to articulate the jawassembly 34 about an axis perpendicular to a longitudinal axis of theloading unit 30 between a non-articulated configuration (FIG. 16) and anarticulated configuration (FIG. 17). The articulation member 52 isslidably disposed within the inner housing 62 and outer tube 32. Anarticulation bar arm 52 a is positioned at the proximal end of thearticulation member 52 and is engaged by the adaptor 20 to facilitatelongitudinal translation of the articulation member 52 upon actuation ofthe adaptor 20. The distal end of the articulation member 52 includes anopening 52 b (FIG. 4) that receives the articulation pin 56 (FIG. 2).The articulation pin 56 passes through the opening 52 b into themounting member 53. The mounting member 53 is secured to the proximalend of the jaw assembly 34 and is pivotally connected to the innerhousing 62 by the articulation pivot 54. As the articulation member 52is advanced within the inner housing 62, the articulation pin 56, whichis offset from the longitudinal axis of the jaw member assembly 34 andarticulation pivot 54, pivots mounting member 53 to articulate the jawassembly 34 (FIG. 28). It is understood that as the articulation member52 is retracted, the articulation pin 56 will pivot the mounting member53 in the opposite direction to pivot the jaw assembly 34 in theopposite direction. Each of the carriage drive bars 41, 43, the cradledrive bars 42, 44, and the knife drive member 95 is flexible tofacilitate actuation of the loading unit 30 when the jaw assembly 34 isarticulated.

Referring now to FIGS. 18-22, operation of the stitching assembly 80 isdescribed in accordance with the present disclosure with an exemplaryupper cradle 46 and an exemplary upper carriage 45. As illustrated, anupper carriage drive bar 41 is connected to the upper carriage 45 and anupper cradle drive bar 42 is connected to the upper cradle 46.

Each upper carriage 45 includes a pair of distally located, spacedsidewalls 45 a. Each of the sidewalls 45 a defines an at least partiallycurved or arced cam slot 82. The upper cradle 46 includes curved orarced cams 83 which protrude from each side of the upper cradle 46. Theupper cradle 46 defines suture passages 63 (FIG. 20) which extendthrough the upper cradle 46. A hollow curved or arced needle 81 issecured to the upper cradle 46 adjacent each suture passage 63 such thata suture 61 (FIG. 2) may pass through the suture passage 63 and out adistal end of the needle 81 as detailed below. The arc of the cam slot82 is substantially similar to the arc of the needles 81. Each cam 83 ofthe upper cradle 46 is received within a respective cam slot 82. Adistal end of the upper carriage 45 defines plows 49. One plow 49 isaligned with a distal end of each of the needles 81. As shown, eachcradle 46 may support a pair of needles 81 with a pair of sutures 61associated with each pair of needles 81 as detailed below.

The distal end of the upper cradle drive bar 42 includes a cradle drivefinger 84 which is operatively associated with the upper cradle 46. Thecradle drive finger 84 translates the upper cradle 46 between aretracted configuration (FIGS. 18 and 19) and an advanced configuration(FIGS. 21 and 22). As shown in FIG. 19, the distal end of the cradledrive finger 84 is secured to an upper surface of the upper cradle 46.As the cradle drive bar 42 is advanced to advance the cradle drivefinger 84 the cam 83 of the cradle 46 is advanced through the arced camslot 82. To accommodate the movement of the cradle 46, a portion of thecradle drive finger 84 is curved or flexible to bend as the upper cradle46 moves through a curved or arched path defined by the arced cam slot82. When the upper cradle 46 is advanced distally towards the advancedconfiguration, the cams 83 of the upper cradle 46 translate within thecam slots 82 of the upper carriage 45 to advance the needles 81 along anarced path. As the needles 81 are advanced in relation to the uppercarriage 45 which is held stationary as the upper cradle 46 is advanced,the body of each needle 81 tracks the distal end of the needle 81 suchthat the body of the needle 81 passes through a hole in tissue createdby the distal end of the needle 81. When the needles 81 are retracted inresponse to retraction of the cradle drive bar 42, the body of eachneedle 81 passes back through the hole in the tissue such that thedistal end of the needle 81 is withdrawn from the tissue. It will beunderstood, that the lower carriages 47 and lower cradles 48 aremanipulated in a similar manner to the upper carriage 45 and the uppercradle 46 described above.

FIGS. 23 and 24 illustrate another embodiment of the presently disclosedcradle drive bar 42′ and cradle 46. As illustrated the cradle drive bar41′ includes a cradle drive finger 84′ having a toothed rack 85′. Thecradle 46′ supports a pinion 86′ which meshes with the toothed rack 85′.The cradle drive finger 84′ is substantially rigid such that as thecradle drive finger 84′ is longitudinally translated as a portion of thetoothed rack 85′ remains engaged with the pinion 86′ of the cradle 46′to transition the cradle 46′ between the retracted and advancedconfigurations. It is noted that the cradle 46′ is supported by thecarriage 45.

With reference to FIGS. 4 and 25-28, the stitching loading unit 30includes a suture storage and delivery assembly 60 disposed generallybetween the outer tube 32 and inner housing 62. The suture storage anddelivery assembly 60 includes sutures 61 and a suture tensioner 68. Theinner housing 62 defines suture recesses 64 which are separated byannular rings 64 a. Portions of sutures 61 are wound around the innerhousing 62 within the suture recesses 64. The sutures 61 associated witheach pair of needles 81 of a respective cradle 46, 48 are stored inpairs in each suture recess 64. The inner housing 62 also definesconduit grooves 66 (FIG. 4) which extend between the suture tensioner 68and each of the suture recesses 64. A conduit 65 is disposed within eachof the conduit grooves 66. A length of the sutures 61 is wound aroundthe inner housing 62 within a suture recess 64, along the conduits 65and through the suture tensioner 68. The suture tensioner 68 includestensioning fingers 68 a (FIG. 27) that engage the sutures 61 to preventlengths of sutures 61 from inadvertently being drawn through the suturetensioner 68. In addition, the suture tensioner 68 permits stitch loopsto be formed as detailed below. The sutures 61 are fed from the suturetensioner 68, through the suture passages 63 of cradle 46, 48, andthrough needles 81. The conduits 65 prevent interference between theportion of the sutures 61 wound about the inner housing 62 and theportion of the suture 61 extending through the conduit grooves 65.

When the cradles (e.g., lower cradle 48) are in the retracted position(FIG. 26), the needles 81 associated with the cradle are recessed withinthe needle slots 39 of a respective jaw member (e.g., lower jaw member38) beneath a tissue engaging surface 100 of a respective jaw member 36,38. The sutures 61 extend from the distal end of each needle 81 with aportion positioned along an outer surface of the needles 81. When theneedles 81 are advanced from the retracted position to the advancedposition (FIG. 25), the needles 81 extend from the needle slots 39across the tissue engaging surface 100 of the respective jaw member 36,38 (e.g., lower jaw member 38). As the needles 81 are moved from theretracted position toward the advanced position, a portion of the suture61 is trapped between the outer surface of the needle 81 and the plow 49such that as the needle 81 moves an additional portion of sutures 61 aredrawn through the suture tensioner 68. Then, as the needles 81 arereturned back to the retracted position within the needle slots 39, aloop is formed from a portion of the sutures 61 as detailed below.

Referring to FIGS. 29-38, the operation of the stitching loading unit 30is detailed in accordance with the present disclosure. In a fullyretracted position of the drive bar assembly 40 (FIGS. 29-31) the upperand lower jaws 36, 38 are in an open configuration, the upper and lowercradles 46, 48 are in the retracted position, and the I-beam 94 is inits proximal-most position. The proximal end of the beam grooves 98include ramps 99 (FIG. 31). In the proximal-most position of the I-beam94, the flanges 97 of the I-beam 94 are positioned proximal to the ramps99 of the beam grooves 98. One of the upper and lower jaw members 36, 38may include a shield 31 (FIG. 29) to prevent premature engagement oftissue with the knife 92.

With tissue (not shown) positioned between the upper and lower jawmembers 36, 38, the upper carriage drive bars 41 (FIG. 11) can belongitudinally advanced within the jaw assembly 34 to advance the knifedrive member 95. As discussed above, the upper carriage drive bars 41are engaged with the upper cradle drive bars 42 such that when the uppercarriage drive bars 41 are advanced the upper cradle drive bars 42 arealso advanced. As the knife drive member 95 is advanced, the knife drivemember 95 advances the I-beam 94 to advance the flanges 97 along thebeam grooves 98 of the upper and lower jaw members 36, 38 as shown inFIGS. 32 and 33. As the flanges 97 advance into the beam grooves 98, theflanges 97 of the I-beam 94 engage ramps 99 to cam the jaw members 36,38 to the clamped configuration.

After the upper and lower jaw members 36, 38 are in the clampedconfiguration, the drive bar assembly 40 (FIG. 10) can be advancedfurther to translate the carriages 45, 47 and the cradles 46, 48 throughthe jaw assembly to create stitches with the sutures 61 in tissueclamped between the jaw members 36, 38. The carriages 45, 47 and cradles46, 48 advance through the jaw assembly in a stepped manner. Forexample, the carriage 45 and the cradle 46 are advanced together (afirst step) to a first suture location. Next, the cradle 46 is advancedand retracted relative to the carriage 45 to move a needle 81 throughtissue to apply a suture loop to tissue. Then the carriage 45 and thecradle 46 are advanced together to a second suture location as detailedbelow. This process is repeated to form suture loops along the length ofthe jaw assembly 34.

Referring to FIG. 34, the upper carriage 45 is advanced, which alsoadvances the upper cradle 46, to a position within the jaw assembly 34.Next, with the upper carriage 45 longitudinally fixed, the upper cradle46 is advanced to extend needle 81 a from the needle slot 39 a of theupper jaw member 36, through tissue clamped within the jaw assembly 34,and into the needle slot 39 b of the lower jaw member 38. The suture 61a, which passes through needle 81 a, is pinched between the plow 49 aand the outer surface of needle 81 a as the needle 81 a is moved suchthat a length of suture 61 a is drawn through the suture tensioner (FIG.27). As the needle 81 returns to its retracted position, the length ofsuture 61 a forms a first stitch loop 161 (FIG. 35) on the lower side ofthe tissue clamped within the jaw assembly 34 and adjacent the lower jawmember 38. It is contemplated that a portion of the first stitch loop161 may be disposed within the needle slot 39 b of the lower jaw member38.

With reference to FIG. 35, when the first stitch loop 161 is formed, theupper cradle 46 is returned to the retracted position within the needleslot 39 a of the upper jaw member 36 leaving the first stitch loop 161on the lower side of tissue clamped within the jaw assembly 34 andadjacent the lower jaw member 38. Next, the lower carriage 47 and thelower cradle 48 are advanced to locate the distal end of the needle 81 bof the lower cradle 48 in a position to pass through the first stitchloop 161.

Referring to FIG. 36, with the lower carriage 47 longitudinally fixed,the lower cradle 48 is advanced to extend the needle 81 b from theneedle slot 39 b of the lower jaw member 38, through the first stitchloop 161, through tissue clamped within the jaw assembly, and into theneedle slot 39 a of the upper jaw member 36. The suture 61 b, whichpasses through needle 81 b, is also pinched between the plow 49 b andthe outer surface of the needle 81 b as the needle 81 b is extended todraw a length of suture 61 b through the suture tensioner (FIG. 27). Thelength of suture 61 b forms a second stitch loop 162 on the upper sideof tissue clamped within the jaw assembly 34 distal to the first stitchloop 161 and adjacent the upper jaw member 36.

With reference to FIG. 37, when the second stitch loop 162 is formed,the lower cradle 48 is returned to the retracted position within thelower jaw member 38 leaving the second stitch loop 162 on the upper sideof tissue clamped within the jaw assembly 34 adjacent the upper jawmember 36. The upper carriage 45 is advanced within the jaw assembly 34(a second step) to also advance the upper cradle 46 to locate the distalend of needle 81 a of the upper cradle 46 in a position to pass throughthe second stitch loop 162. As the upper carriage 45 is advanced, theknife 92 is advanced to sever tissue clamped within the jaw assembly 34.It will be appreciated that to reduce bleeding, the knife 92 trails thenewly formed stitch loops (e.g., stitch loops 161, 162) by at least onestitch loop.

Referring to FIG. 38, with the upper carriage 45 longitudinally fixed,the upper cradle 46 is advanced to extend needle 81 a from the needleslot 39 a of the upper jaw member 36, through the second stitch loop162, through tissue clamped within the jaw assembly 34, and into theneedle slot 39 b of the lower jaw member 38. As discussed above, thesuture 61 a is pinched between the plow 49 a and the outer surface ofneedle 81 a as the needle 81 a is extended to tension the first stitchloop 161 on the second stitch loop 162 and to draw an additional lengthof suture 61 a through the suture tensioner 68 (FIG. 27). The additionallength of the suture 61 a forms a third stitch loop 163 on the lowerside of tissue clamped within the jaw assembly 34. The tensioned stitchloops form stitches.

This process is repeated to form additional stitches until the carriages45, 47 reach the end of the jaw members 36, 38 or until a desiredportion of tissue is stitched and cut (e.g., a body lumen is sutured anddissected). To open the jaw members 36, 38, the drive bar assembly 40 isreturned to the fully retracted position to withdraw the flanges 97 ofthe I-beam 94 from the beam grooves 98 releasing the jaw members 36, 38from the clamped configuration. The suture tensioner 68 maintainstension in the sutures 61 to continuously stitch an additional portionof tissue clamped within the jaw assembly 34. When the desired portionof tissue is stitched and cut, the excess of sutures 61 a, 61 b istrimmed.

If additional tissue stitching and cutting is required, the jaw assembly34 is advanced over additional tissue and the process is repeated untilthe desired portion of tissue is stitched and cut.

It is contemplated that stitching loading unit 30 may define openings inthe outer tube 32 proximal to the suture tensioner 68 permitting lengthsof the sutures 61 to be stored external to the stitching loading unit30. It will be understood that storing lengths of the sutures 61external to the stitching loading unit 30 may permit the stitchingloading unit 30 to be used indefinitely.

Although the jaw members 36, 38 of the jaw assembly 34 are illustratedas being substantially linear, it is contemplated that jaw members 36,38 of jaw assembly 34 may be curved along a length thereof. An exemplaryembodiment of such a curved jaw assembly is disclosed in commonly ownedU.S. Pat. No. 7,988,028, the contents of which are incorporated hereinby reference in its entirety.

While several embodiments of the disclosure have been shown in thedrawings, it is not intended that the disclosure be limited thereto, asit is intended that the disclosure be as broad in scope as the art willallow and that the specification be read likewise. Any combination ofthe above embodiments is also envisioned and is within the scope of theappended claims. Therefore, the above description should not beconstrued as limiting, but merely as exemplifications of particularembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the claims appended hereto.

What is claimed:
 1. An end effector comprising: a first cradle; a firstcarriage moveably supporting the first cradle along a first curved pathbetween an advanced position and a retracted position relative to thefirst carriage; a first needle supported by and extending distally fromthe first cradle; a first suture supported by the first needle, thefirst cradle and the first carriage configured to draw the first suturethrough tissue when the first cradle moves towards the advanced positionand configured to form a first stitch loop in the first suture when thefirst cradle is moved from the advanced position towards the retractedposition; a second needle; and a second suture supported by the secondneedle, the second needle configured to draw the second suture throughthe first stitch loop.
 2. The end effector according to claim 1, whereinthe first carriage includes a first plow positioned adjacent a distalportion of the first needle, the first plow being configured to capturethe first suture against an outer surface of the first needle as thefirst needle is moved towards the advanced position.
 3. The end effectoraccording to claim 1, wherein the first carriage defines a cam slot andthe first cradle includes a cam received within the cam slot of thefirst carriage.
 4. The end effector according to claim 3, wherein thefirst needle is curved.
 5. The end effector according to claim 4,wherein the cam slot of the first carriage is curved and defines thefirst curved path of the first cradle.
 6. The end effector according toclaim 5, wherein the first curved path has a curvature that correspondsto a curvature of the first needle.
 7. The end effector according toclaim 1, further comprising: a second cradle supporting the secondneedle such that the second needle extends distally from the secondcradle; and a second carriage moveably supporting the second cradlealong a second curved path between an advanced position and a retractedposition relative to the second carriage, the second suture forming asecond stitch loop as the second needle is moved from the advancedposition towards the retracted position.
 8. The end effector accordingto claim 7, wherein the second carriage includes a second plowpositioned adjacent a distal portion of the second needle, the secondplow being configured to capture the second suture against an outersurface of the second needle as the second needle is moved towards theadvanced position.
 9. A loading unit comprising: an inner housing havingproximal and distal portions; a first jaw member supported by the distalportion of the inner housing and defining a first needle slot extendingin a direction parallel to a longitudinal axis of the first jaw member;a second jaw member supported by the distal portion of the inner housingand defining a second needle slot extending in a direction parallel to alongitudinal axis of the second jaw member, the first and second jawmembers moveable relative to one another between an open position and aclamped position; a first cradle; a first carriage moveably supportingthe first cradle along a curved path between an advanced position and aretracted position relative to the first carriage; a first needlesupported by and extending distally from the first cradle; a firstsuture supported by the first needle, the first cradle moveable inrelation to the first carriage to advance the first needle from thefirst needle slot towards the second needle slot and to retract thefirst needle from the second needle slot back within the first needleslot, the first cradle and the first carriage drawing the first suturethrough tissue when the first cradle as the first cradle advances and toform a first stitch loop in the first suture when the first cradle isretracted; a second needle; and a second suture supported by the secondneedle, the second needle drawing the second suture through the firststitch loop.
 10. The loading unit according to claim 9, wherein thefirst carriage includes a first plow positioned adjacent a distalportion of the first needle, the first plow being configured to capturethe first suture against an outer surface of the first needle as thefirst needle is advanced towards the second needle slot.
 11. The loadingunit according to claim 9, further comprising: a second cradlesupporting the second needle such that the second needle extendsdistally from the second cradle; and a second carriage moveablysupporting the second cradle such that the second needle advances fromwithin the second needle slot towards the second needle slot andretracts the second needle from the first needle slot back within thesecond needle slot, the second suture forming a second stitch loop asthe second needle is retracted.
 12. The loading unit according to claim11, wherein the second carriage includes a second plow positionedadjacent a distal portion of the second needle, the second plow beingconfigured to capture the second suture against an outer surface of thesecond needle as the second needle is advanced towards the first needleslot.
 13. The loading unit according to claim 9, further comprising asuture storage and delivery assembly including: a suture tensioner; afirst suture recess defined by and along a length of the inner housingproximal to the suture tensioner; a second suture recess defined by andalong a length of the inner housing proximal to the first suture recess;a groove defined in the inner housing through the first suture recessand into the second suture recess; a conduit disposed within the groove;a portion of the first suture being configured to wind around the innerhousing in the first suture recess, pass through the suture tensioner,and pass through the first needle; and a portion of the second suturebeing configured to wind around the inner housing in the second suturerecess, pass through the conduit, pass through the suture tensioner, andpass through the second needle.
 14. The loading unit according to claim9, further comprising a drive bar assembly disposed within the innerhousing, the drive bar assembly having: a first carriage drive barincluding a distal portion connected to the first carriage to move thefirst carriage within the first jaw member; and a first cradle drive barincluding a distal portion operatively associated with the first cradleto advance and retract the first cradle relative to the first carriage.15. The loading unit according to claim 14, wherein a proximal portionof the first cradle drive bar is disposed over the first carriage drivebar distal to a proximal end of the first carriage drive bar such thatthe first cradle is advanced with the first carriage.
 16. The loadingunit according to claim 14, wherein the distal portion of the firstcradle drive bar includes a cradle drive finger operatively associatedwith the first cradle.
 17. The loading unit according to claim 16,wherein the cradle drive finger is flexible and a distal portion of thecradle drive finger is fixed to a surface of the first cradle such thatwhen the first cradle is in an advanced position, the cradle drivefinger forms an arc with a surface of the first cradle.
 18. The loadingunit according to claim 16, wherein the cradle drive finger issubstantially rigid and includes a toothed rack and a surface of thefirst cradle includes a pinion, the toothed rack engaging the pinion tomove the first cradle between the retracted and advanced positions. 19.The loading unit according to claim 9, further comprising a knifeassembly, the knife assembly including: an I-beam positioned within andlongitudinally translatable within a knife slot, the knife slot definedabout the longitudinal axis of each of the first and second jaw members,the knife slot extending from a proximal portion of each of the firstand second jaw members towards a distal end of each of the first andsecond jaw members; and a knife defined by the I-beam.
 20. A stitchingassembly comprising: a first jaw member; a second jaw member; a firstneedle moveable in a stepwise manner distally through the first jawmember, the first needle being moveable from a retracted position inwhich the first needle is disposed within the first jaw member to anadvanced position in which the first needle is extended from the firstjaw member towards the second jaw member; a first suture associated withthe first needle; a second needle moveable in a stepwise manner distallywithin the second jaw member, the second needle being moveable from aretracted position in which the second needle is disposed within thesecond jaw member to an advanced position in which the second needle isextended from the second jaw member towards the first jaw member; and asecond suture associated with the second needle; a first drive barconfigured to, at each step of movement of the first needle, move thefirst needle from the retracted position to the advanced position and toreturn the first needle to the retracted position to form a first sutureloop in the first suture through tissue and adjacent the second jawmember; and a second drive bar configured to, at each step of movementof the second needle, move the second needle from the retracted positionto the advanced position through a suture loop of the first suture andto return the second needle to the retracted position to form a secondsuture loop in the second suture through tissue and adjacent the firstjaw member.